To systematically understand the water radiolysis in oxygenated condition for electrons, the energy deposition patterns and reactions of chemical species produced in water were investigated as a function of electron energy (100eV-1MeV) by the method of Monte Carlo simulation. It was shown that the energy deposition patterns and the initial distributions of chemical species on a scale of several tens of nm are essential to determine the following chemical yields. An apparent change in the yields and reaction processes of chemical species was observed in connection with these parameters. Moreover, the dose effect on the chemical reactions and the yields of chemical species were analyzed. The chemical reactions in the presence of OH radical scavenger were also examined.